Kenwood TM-271A Service Manual page 40

P Q
DISPLAY UNIT (X54-3450-10)
MHz & MENU
ADJUASTMENT
S1
W02-3665-05
C39
ENCODER
0.1u
D31
R55
0
1SS355
R47
47k
J1
8
MBL(Key A)
R48
8C
GND
47k
PTT
ME
MIC
HOOK
CM
1
CN1
18 MIC
17 ME
16 GND
15 PTT
14 BRI
13 RXD
12
POWER
11 VOL
10 8C
9
5C
8 DO
7 CL
6
CE
5 DI(from LCD)
4 MIC KEY
3 ENCODER B
2 CM
1 ENCODER A
X57-685X-XX C203
0-10 K 0.027u 1000p
0-21 M2 0.027u 1000p
TM-271A 144-148MHz
0-22 M3 0.027u 1000p
0-23 M4 0.027u 1000p
TM-271E 144-146MHz 2-71 E 0.047u
Note : The components marked with a dot (•) are parts of layer 1.
R
SCHEMATIC DIAGRAM
MR VFO CALL
REV Func
49
NC
50
KI1
51
KI2
52
4.96V
KI3
53
ON/OFF & VOLUME
NC
ADJUASTMENT
54
NC
4.94V
55
NC
VR1
R46
R31-0646-05 56
VDD
57
100
VDD1
58
VDD2
59
VSS
VARIABLE 60
RESISTOR OSC
61
DO (to cpu)
62
CE
63
CL
64
CP1
DI (from cpu)
R90-0724-05
4.96V
L1
R21 R22 R23
10k 10k
10k
7.90V
KEY BACKLIT SWITCH
KEY ILLUMINATION
Q10
D2 D3 D4
KRA225S
R10
1.2k
B30-2205-05
D2-4
KEY BACKLIT
4.80V(BRIGHTNESS MAX)
Q6
0V(BRIGHTNESS OFF)
KRC102S
DC SWITCH
C206 C207 C614 R119 R120 R121 R204
0.022u NO 0 0 0 18k
0.022u NO NO NO NO 18k
0.022u NO 0 NO NO 18k
0.022u NO 0 0 NO 18k
680p 0.039u 3p 0 NO 0 10k
S
TM-271A/271E
LCD (B38-0885-05)
32
31
SEG27
SEG26
30
SEG25
29
SEG24
28
SEG23
27
SEG22
26
SEG20
LCD CONTROLLER
25
SEG20
IC3
24
PT6554LQ
SEG19
or
23
LC75854W
SEG18
22
SEG17
21
SEG16
20
SEG15
19
SEG14
18
SEG13
SEG12
17
LCD BACKLIT SWITCH
7.90V 7.10V
Q9
2SB1132(Q,R)
R49
56
R41
7.30V
56
R50
56
R54
Q12
56
UMG3N
R8
5.02V
1k
DIMMER
FUNCTION
SWITCH
R207
750k
750k
750k
750k
1M
T
LCD ILLUMINATION
D19 D20 D21
B30-2205-05 B30-2205-05 B30-2205-05
D22 D23 D24
B30-2205-05 B30-2205-05 B30-2205-05
D25 D26 D27
B30-2205-05 B30-2205-05 B30-2205-05
D28 D29 D30
B30-2205-05 B30-2205-05 B30-2205-05
D19-30
LCD BACKLIT
37
X54-345 1/1
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